Step 1: How to Begin:

Step 2: Backward-Forward Knot

Start with the right-most string (orange). A forward-backward knot is simply a forward knot then a backward knot. So bend the orange string over the blue string so the end is towards the center. Pull the end under and through the bend you just made. Now using the same orange string make a foward knot (end pointing away from center) on the same blue string.
The order should be the same as before : 1 2 3 4 4 3 2 1

Step 3: Backward Knot

Now use the blue string to make 2 backward knots (1 on purple 1 on pink). The order should be: 1 2 3 4 2 3 4 1

Step 4: Forward-Backward Knot

Now using the left orange you should do a forward-backward knot on the left blue string. A forward the end points toward the center and a backward away from the center. The order should not have changed from the last step.

Step 5: Forward Knot

Now do 3 forward knots using the left blue string (1 for purple, 1 pink, 1 other blue)
The order should be: 1 3 4 2 2 4 3 1